1. Field of the Invention
This invention relates to a fluid-filled engine mount device through which a power unit is mounted on a support body, and more particularly to the fluid-filled engine mount device having the function of a dynamic damper.
2. Description of the Prior Art
It is well known in the art that a fluid-filled engine mount device is used between an automotive engine side and a vehicle body frame side to damp the vibration caused by the bound and rebound of the vehicle body. The fluid-filled engine mount device is in general so configured that a hollow rubber block is securely interposed between upper and lower base plate members which are connected to the engine side and the body frame side, respectively. The hollow of the rubber block serves as a fluid chamber filled with a fluid, and the fluid chamber is in communication through an orifice of a partition plate member with an auxiliary chamber. Fluid flow takes place between the fluid and auxiliary chambers in response to the vibration applied to the engine mount device, thereby absorbing input vibration by virtue of the restricted fluid flow through the partition plate member orifice.
In addition to the engine mount device, a dyanmic damper is installed between the engine side and the vehicle body side in order to damp high frequency fine vibration transmitted from the engine to the vehicle body which vibration causes a booming noise within the passenger compartment. The dynamic damper is so arranged as to produce a resonant vibration in response to the above-mentioned high frequency fine vibration.
However, since the dynamic damper is installed separately and independently from the engine mount device, a relatively large space is required for both of them within a relatively narrow engine compartment. Besides, using two implements for the purpose of vibration damping is disadvantageous from the standpoints of weight-lightening and production cost.